Methodology Association of periOperative Registered Nurses (AORN) guideline is used as the conceptual framework of this study including evidence based practice for smoke and bio-aerosols evacuation systems. The study design is a quasi-experimental study (manipulation and control only, without randomization) comparing the amount of surgical smoke and bio-aerosols particles pre- post smoke evacuation uses. The samples consist of 64 cases of surgical patients who receive head-neck or breast surgery and 64 cases of surgical patients who receive abdominal laparoscopic surgery. The amount of surgical smoke and bio-aerosols' particles in the surgical field and OR environment are measured by AeroTraxTM Handheld Airborne Particle Counter Model 9306.